I design, build, fix, and extend production backend services using Kotlin, Java, and Spring Boot.
I have 8+ years of JVM software development experience across mobile backends, real estate, logistics, agritech, fitness, e-commerce, and internal business platforms.
Services include:
• REST API design and implementation
• Spring Boot MVC and WebFlux development
• Kotlin and Java backend services
• PostgreSQL and MySQL integration
• R2DBC, JPA, Hibernate, and jOOQ
• Spring Security, JWT, and OAuth2
• Redis caching and session management
• WebSocket and real-time communication
• RabbitMQ and asynchronous processing
• External API and payment integrations
• Flyway database migrations
• OpenAPI and Swagger documentation
• Resilience4j retries and circuit breakers
• Docker and Docker Compose configuration
• Unit and integration testing with JUnit, MockK, Mockito, and Testcontainers
• Performance investigation and production bug fixing
I can work with an existing backend or develop a new service from defined requirements. The implementation will follow clean architecture principles, clear API contracts, database migration practices, and automated testing.
Please send the requirements, current architecture, API documentation, error logs, and relevant project files. I will review the scope and propose a clear implementation plan.